


The Substitute

by WellDoneBeca



Category: Supernatural
Genre: Eventual Smut, F/M, Out of Character, Teacher Castiel, University, Vaginal Fingering, Vaginal Sex
Language: English
Status: Completed
Published: 2018-05-01
Updated: 2018-05-10
Packaged: 2019-04-30 21:00:44
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,725
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14505390
Author URL: https://archiveofourown.org/users/WellDoneBeca/pseuds/WellDoneBeca
Summary: You couldn’t concentrate. You simply couldn’t. Professor Castiel could be saying the most intelligent stuff or the biggest bullshit now, but you honestly had no idea. All you could see was how hot he was.Dammit. People like him weren’t supposed to be teaching, they were supposed to be on TV or something.





	1. Part 1

You frowned at the text reminding you to show up for Christian Theology class.

Your teacher – a middle age woman far too homophobic for your own taste – had died a week or two weeks ago, leaving you with your Fridays free. Apparently, they’d found a substitute now, which completely blew your plans to crash on your friend’s place – which was fairly close to the university - and take a nap until it was time to go to the next class.

You cursed under your breath, changing your direction and trying not to look  _too_ grumpy as you walked back.

The room was still empty when you came in, sitting in your usual spot and pulling your laptop out. When the time came, not even half of the class had shown up, and neither did the apparent professor.

_They are a substitute and are late already. Wow, great impression._

Just a minute after you rolled your eyes in annoyance, a man walked past the door and lips parted open in response. Well, that wasn’t what you expected for a substitute.

That was the hottest man you’ve ever met.

“Morning, class,” he looked around awkwardly. “I’m professor… Romanov,” he wrote the name o the board. “But you can call me Castiel.”

You frowned. Castiel?

“Like the angel of Thursdays?” you said out loud, not able to control yourself, and he looked directly at you.

“Indeed,” he confirmed. “Like the angel of Thursdays.”

You leant back in your chair surprised.

_Well, ain’t that meta?_

“Now, can anyone fill me up about your previous professor’s program?”

You couldn’t concentrate. You simply couldn’t. The substitute – Professor Castiel Romanov – could be saying the most intelligent stuff or the biggest bullshit now, but you honestly had no idea. All you could see was how hot he was.

His arms were ripped and his lips the most pinkish and delicious you’ve laid your eyes on. His eyes were extremely blue, and you wondered how the rest of his body looked like without that many clothes on. Dammit. People like him weren’t supposed to be teaching, they were supposed to be on TV or something.

You couldn’t help as your mind wondered through scenarios and more scenarios involving him and  _you_ doing very inappropriate stuff. And it wasn’t even for a single day. At the second half of your third class with him, your thoughts were so far and so dirty you could even feel yourself getting wet anytime you passed through him in the corridor. You were so focused on him that the weird stuff happening around the campus wasn’t even concerning you anymore.

“Watch out!” you heard a bit far from you while walking out of the room, and turned to your side just in time to see the janitor raising his hand to warn you about something before falling back on the wet floor, making your books fly and land all around. You, though, never felt the fall. Instead, you felt on a body behind you, and arms holding you.

“Shit!” you exclaimed in surprise and heard a chuckle behind you, turning around to look at whoever had saved you.

Professor Romanov.

You put yourself on your feet, straightening your clothes.

“Professor!” You managed to let out, stepping back and feeling your cheeks burning in embarrassment.

“Are you okay?” he questioned, worried.

“Yes,” you nodded quickly. “Thank you.”

He smiled softly at you, kneeling down and picking the closest book from his feet and gave it to you.

“Be careful next time,” he reminded you.

“Of course,” you nodded. “Thank you.”

You left the room for the most awkward walk and smiled politely to the overly tall green-eyed janitor when he offered you the other books, muttering a ‘thanks’ and walking to your friend.

“What’s happening with the men in this place?” you whispered to your friend when you reached her. “The janitor, the new professor…”

“Well, have you stepped on the library lately?” she smirked. “There is a 6 something feet tall long haired dude replacing our old librarian.”

You looked at her in surprise for a moment.

“Wow,” you whispered. “Got any number?”

She shrugged.

“Not really. He is very  _professional._ ”

You rolled your eyes and chuckled.

“Okay, then,” you checked your clock. “Come on. We gotta go.”

* * *

 

The parking lot was silent and empty as you waked in your car’s direction. You were really late now, being the last one leaving your class after spending almost an hour with your professor, keeping your notes tidy. She was still in her office now, but you were tired enough to just wrap your stuff up and just get home.

You were used to doing that, but today was the first time it had a  _weird_ feeling to it. It was relatively colder than normal and extremely silent. You couldn’t even hear the wind or the cicadas that were usually around.

Something was very wrong.

You heard a noise behind you and turned to look where the sound had come, seeing nothing. A second later, though, you heard a yell.

 “Get down!”

You didn’t have a reason to obey but did it the same way. After you  _blinked,_ there was a loud impact just where you’d been. You turned to your side, and your eyes widened instantly when a weird figure launched itself on you, open its mouth wide. It was monstrous, with some sort of dog’s mouth and long claws, holding tightly and ready to kill and  _eat_ you.

_Oh fuck._

“Hey!” a man shouted by your side and the thing was pushed away, leaving cuts in both your arms and a very startled you.

_Wait… Was that the janitor?_

“Cas, get her out of here!” the janitor yelled somewhere and you raised your eyes to find no one less than Professor Romanov by your side, wearing a long trench coat and blue tie.

“Come on,” he pulled you by your hand. “Let’s go.”

You didn’t even feel when he pulled you the place  _literally_ shifted around you. Now, you were inside a completely strange room.

“What the fuck!” you yelled.

“Stay here,” he held you down. “I’ll be back and explain it to you, but please stay here.”

With that, he was gone.

What the fuck was going on?


	2. Part 2

You head was spinning from adrenaline and fear. You didn’t know what was going on, what’d just happened or where you could possibly be. Your phone wasn’t with you, but inside the purse you’d just left under your car, you were completely alone, you had a bunch of cuts in both your arms and your  _fucking substitute was fighting a monster alongside with the janitor!_

God, you were panicking.

You waited and waited and, when professor Romanov finally showed up, you were more pissed than scared. He looked flawless and you could finally look at his full outfit. Under the trench coat, you could see a suit, a white shirt and the blue tie that matched his eyes. Somehow that made him look even hotter.

“Hello, Y/N,” he stood in front of you. “How do you feel?”

You opened your mouth and closed it, breathing deep.

“What the actual fuck?” you finally let out.

He nodded slowly as if he expected you to react that way.

“What was that?”

“A werewolf.”

You stared at him, not being able to say a word for a long moment, opening and closing your mouth.

“A what?”

“Werewolf,” he repeated. “A… Werewolf. There is no other way to name it.”

You stood up and walked around the room for a moment and walked around the chair, looking at him and then started walking again.

“Oh my God,” you whispered, sitting down. “Oh my God. Am I dead? I must be dead.”

“No. You are alive.”

You let the feeling sink in for a moment and your eyes widened.

“Wait, that thing hurt me,” he exclaimed, putting your hands on where its claws had cut your skin. “Am I a werewolf now?”

Professor Romanov shook his head patiently.

“That’s not how it works. You are perfectly safe.”

You sat back on the chair, closing your eyes.

“Fuck.”

You moved your hands and rubbed your face.

“Those things are really… Real?” you exclaimed. “Like in Twilight?”

He took a long breath.

“Not like in Twilight.”

You moved your fingers through your hair once again, sure it was a mess already but not even caring.

“Vampires are real too?”

“Yes,” he nodded.

You shifted on your feet.

“Ghosts? Demons? Grims? Wizards? Hogwarts? Dragons? Skinwalkers?”

He was taken back for a moment with the way you shot words at him but didn’t interrupt you or laughed at your reaction.

“Ghosts, demons, dragons and skinwalkers, yes,” he confirmed. “Hogwarts, no. And I’m not sure what a Grim is.”

You took a long breath again, cursing in a whisper.

“How do… How… How do we not know about that? How do people live and… And don’t… It’s all out there?!”

He reached out instantly, holding your hand to calm you down.

“I know it’s a lot,” he affirmed. “But you don’t have to worry.”

“What do you mean I don’t have to worry?” you frowned. “Professor Romanov, there is a world of monsters out there and no one else to protect us from them!”

“Actually,” he squeezed your hand. “There are people fighting them.”

You tilted your head to the side, finally realising what you’ve let go for a moment.

“You and the janitor! That’s why you came here, right? Because you thought there was a werewolf!”

“Yes,” he nodded. “But humans… for years they have been fighting those monsters and protecting people like you.”

The way he phrased that made you stop.

“They?”

“I’m an angel.”

Your lips parted open and you stared at him, surprised and startled.

“You’re kidding me,” you decided. “Now…” you stood up. “Where are the cameras? That is… Stop it. I don’t authorise you do use my image, stop it right fucking now.”

“Y/N, this is serious,” he declared.

You sat down again, running your hands over your face and hair.

“Fuck. That’s…” you felt your breath racing. “That’s… Oh… I’m…”

Before you realised, Castiel moved his hand to your face, touching your forehead with two fingers, and calmness took over you.

“You should go home and sleep,” he decided. “Here. Take my hand.”

You took his offer and held his hand, being rushed to the parking lot by your car again and jumping startled when you saw two men waiting.

“Cas,” the shorter man – the janitor – called. “Is the girl okay?” he pointed at you.

“ _The girl_ can speak,” you interrupted him before the man…  _angel…_ Said anything.

By his side, there was a man even taller, and he walked to you.

“Are you okay?” he questioned, looking into your eyes.

“If by okay you mean I’m alive and trying not to freak completely, yes. I do.”

He eyes the janitor for a moment and offered you a hand.

“I’m Sam. Sam Winchester. This is my brother Dean. You already know Castiel.”

“Nice to meet you, Sam Winchester,” you eyes him up and down, telling you his name. “So you… You two are the dudes that kill the monsters?”

He nodded in confirmation.

“We’ll drive you home,” Dean offered. “Sam can take your car, you must be feeling really tired.”

You rolled your eyes in response.

“Home? Dude, I just got attacked by a werewolf. I need to hit the bar.”

you heard a short laugh and looked at Dean just to find him chuckling.

“Well, ain’t that my kind of girl?”

* * *

You clicked with Dean. The whole time he had talked to you, you had found things in common. He was sociable and a good drinking partner, betting with you over a bottle of beer or and stuff like that. With Sam joining the conversation a bit later, he told you about how they met Castiel – who wasn’t really a professor, but it wasn’t such a surprise now – and the stories the three of them had lived. The whole time, your fake-professor had stayed in silence, watching you and listening to you. You didn’t get drunk – the brothers didn’t let you – but you had fun. It wasn’t like the fact you were attacked by a damn werewolf wasn’t inside your head, but you had eased up a lot.

At some point, Dean was entertained with a girl and Sam had gone to God knows where, which left you and Castiel all alone.

“So,” you cleared your throat. “You’re not a professor.”

“I’m afraid not.”

You nodded slowly and rested a hand on the table in front of you.

“What can you do?” you played with the bottle in front of you. “I mean… As an  _angel._ ”

He glanced at you for a moment and rested back in his chair.

“I’m stronger than humans,” he said nonchalantly. “I’m immortal. I can cast spells. I can read minds…”

Your eyes widened.

“Excuse me?”

He smirked.

“I can read mind, yes.”

Instantly, your mind ran to the moments you were daydreaming in his class, thinking about how you just wanted to jump on his bones, kiss him like there was no tomorrow.  _Did he hear that?_

“I did,’ he confirmed. “It was, indeed, very tempting. You almost made me blew my cover.”

You bit your lip, hesitating, and turned to look at him with a question on the tip of your tongue.

“You already know what I’m gonna say,” you whispered. “You can read minds.”

Castiel smiled, looking down for a moment and then at you.

“Yes,” he decided. “And yes.”


	3. Part 3

Maybe it was the adrenaline, maybe it was the fact you almost died and also discovered everything you thought was the truth was just a lie, and the supernatural was true, but you didn’t even care you were bringing a complete stranger home. Castiel didn’t have a last name and was older than the whole universe; you probably would never see each other again after he left. None of that mattered, though. Right now, you were walking into your small apartment with his lips against yours and his big strong hands were holding you close. In a minute, his trench coat fell on the floor on the way to your room, and you almost hit the side of the door with your arm before he dropped you on the bed.

“Are you sure you want to do this?” you questioned when he moved his lips to your neck. “Aren’t… You…” you panted. “Supposed to be pure?”

Castiel looked at your face with curiosity, stopping, and then lied a chaste kiss on your chin.

“No,” he decided, his voice as thick and warm as his body against you. “I’m free.”

You felt your cheeks arming up and moved your hands to his face, pulling him to a kiss before taking off his suit and moving your fingers over the buttons of his shirt, pulling his tie.

“Take that off,” you whispered and, in a second, you couldn’t feel anything in your hands, and his naked skin was pressed against you – which included his half hard cock against your thigh.

You wanted to ask him what was that, how he could have done that, but Castiel immediately moved down and licked a long stripe on your chest that ended on your nipples, making you gasp. He tested you with his tongue, licking around your areola while staring at you and flicking your nipple right after.

You moaned in response and he smiled, repeating it with the other side.

“You’re beautiful,” he whispered, kissing the middle of your chest gently. “Your skin is soft.”

You sighed when – instead of just rushing to your lad bits like everyone else you’ve slept with had done – he started licking and kissing your torso, not leaving a single inch of your body untouched. Castiel nibbed on your skin from your shoulders to your stomach, completely absorbed in the action until he reached your belly button. Finally, he looked up at you and bit the skin you had right under it and looked up at you.

You were a panting mess, with nipples hard and wetness dripping from your pussy lips to the bedsheets.

“Do you like this?” he asked, not sounding close to a teaser, but genuinely wanting to know the answer.

“Yes,” you whispered. “Your lips feel so good.”

Castiel smiled, and you whimpered when he ran his short nails down your thighs.

“Do you wish me to continue?” he questioned, not even waiting for the answer before he moved down and kissed your right ankle.

You closed your eyes, feeling yourself even wetter. Castiel didn’t even care. He just continued kissing your legs giving both of them equal attention even after you started whining under him, pleading in whispers for something more.

You were going crazy under his lips, and your hips immediately jumped when his thumb encountered your clit, making tiny circles that made you moan shamefully.

“Castiel,” you whined, spreading your legs, and the sound that emerged from his lips made your entrance clench.

“Say it again,” he said darkly. “Say my name again.”

“Castiel,” you moaned and he moved up in a second he was over you, hard cock resting against your folds.

Moving his fingers to your hair, he pulled you close and kissed your lips once again.

“All those classes,” he growled. “Listening to your thoughts, listening to how you wanted me to push you over that desk and have my way with you, not even caring about people seeing it.

You moved your hands to pull him closer, but Castiel stopped you, looking inside your eyes.

“You want it?” he questioned in a whisper. “Still wants me to bend you over and  _fuck_ _you_ _senseless._ ” he used the same words you’ve thought yourself, and you only whined.  

“ _Please._ ”

Castiel used his hands to push your legs spread, and a hand to hold his hard cock.

“How do you want me?” he questioned in a dark whisper.

“Bare,” you whispered. “Fuck me bare, Castiel. I want to feel you all inside me.”

Castiel pushed his cock inside you all at once, which sent a long and dirty moan all the way up your lips, and you squeezed his shoulders firmly.

“Fuck,” you cussed, squeezing your eyes shut as your walls got used to his invasion.

In response, he moved his head to rest in your neck, kissing your skin and squeezing your sides.

“Does it hurt?” he whispered and you shook your head.

“No… I just…” you whispered. “It’s been a while.”

He moved a hand to your face, cupping your cheek, and kissed your lips gently.

“You can move,” you whispered, minutes later, and he pulled himself out of you for a moment before thrusting in again, making the two of you moan. The motion made the two of you moan out loud, and you soon found a rhythm. His lips never left you, sometimes against yours, sometimes on your skin, but never far from you. His moans weren’t more than low sounds echoing in your ears, and he gripped your thighs when you let a longer moan the moment his cock found the most sensitive spot inside you.

“There,” you insisted, squeezing your eyes shut. “ _Castiel_.”

You were already deep into the pleasure when you felt  _something_ warm surrounding your clit and making it throb and you yourself moan loudly in surprise and sharp pleasure.

Castiel bit your lower lip and held your thighs tightly in his hands spreading you more and just aiming at that little special spot, driving you closer and closer to the edge.

“Yes,” you hissed, moving your hands to his hair and pulling his thick locks. “Don’t stop.”

And he didn’t. The strange thing pressing and playing with your clit and his cock, along with his soft moans were everything you needed to reach your orgasm, and when you did, Castiel pulled himself out of you just to turn you around – his arms moving you like you weighted nothing – and put you on fours, penetrating you because pulling your body so his torso was against your back, his hands now free to play with your breasts.

You reached a second orgasm after just a few minutes of that, moaning his name and not caring about the neighbours hearing you while you did so.

You knew Castiel was close to his orgasm when his cock twitched inside you, bigger and harder, and he held you tighter.

“Pull out,” you moaned softly and he complied, taking his cock out of your dripping pussy, and you managed to turn around and push him down enough to take him in your lips. Castiel moaned the moment you circled his cockhead with your tongue, and his fingers tangled in your hair as you started bobbing your head up and down. It wasn’t late until he finally came and pulled you up to a passionate kiss as soon as you swallowed his cum down. The kiss started fiercely but slowed down until just a gentle and kind thing.

“Fuck,” you whispered when he pulled away, the two of you already lied on the pillows. You were sweaty and sticky, and not even sure your legs could hold you if you tried to walk. “Wow.”

You’d just had sex with an angel.

An angel.

_Fuck._

“That’s probably the most memorable thing I’ve ever done in my life,” you whispered.

In response, Castiel only kissed you again, pulling you to his chest, and the strange energy you’ve felt earlier washed over you again. This time, it brought you a clean feeling; your skin wasn’t sticky anymore and, as the feeling filled you, you could also the tiredness sinking into your bones.

“Rest,” he whispered.

“Will you be here when I wake up?” you looked up at him.

“I’ll try to be,” he caressed your arm.

You hesitate and lifted your head, looking at his face.

“What if I want to see you again?”

Castiel didn’t flinch, only shrugged.

“Pray to me,” he instructed. “And I’ll be here as soon as possible.”

You smiled to yourself, laying on his chest again.

_Castiel._

You had a feeling this wouldn’t be the last time you would see him in your life. You really hoped you were right.


End file.
